Digital video is being used in an increasing array of applications ranging from personal computers (PC) and videoconferences to digital televisions (TVs), set-top boxes, and personal video recorders (PVR). These varied video systems process content that ranges from cable, satellite, and terrestrial broadcasts to streaming video and video-on-demand over the Internet. Due to wide proliferation of storage and transmission of digital content, studios and content providers are getting increasingly concerned about security of their high-quality digital content. It is highly desired by the content-providing community to prevent unauthorized copying and piracy.
In particular, the fast-growing PVR systems allow consumers to interactively choose high quality content from either broadcast media or video-on-demand, and when to watch it. The PVR systems allow consumers control, management rights, and personalization options on digital content. To enable these features, hours and hours of audio-video content are stored on loosely coupled, long-term, often removable storage media that may be accessible to unauthorized individuals.
Another area of concern is conditional access schemes in set-top boxes that are implemented using a removable Smart Card. When the Smart Card is connected with a smart card interface of a decoder chip, the descrambling keys stored on the Smart Card are moved to the decoder chip, which then uses them to descramble the digital content received from a broadcast medium. No security measures are currently provided to prevent an intruder from obtaining the descrambling keys from the smart card interface of the decoder chip.